One the one hand, I suspect a great number of Catholics would like to exchange their consent before the Pope, but on the other hand, I suspect a great many brides would also be concerned about losing control of the ceremony and many of the decisions of the day.
In the United States of America (and perhaps elsewhere), young girls grow up continually - and wrongly - being told that their wedding is "your day." Nothing could be further from the truth, as such a "mass" wedding ceremony indicates (one which the Church's ritual foresees).
When I served in parishes, I made it a point at my first meeting with a couple seeking to be married to especially point this out to them. My words usually went something like this (with the couple looking at me rather speechless):
(Looking first to the bride:) Your wedding day is not about you. (Looking next to the groom:). Your wedding day is also not about you. (Looking to the both of them:). Your wedding day is not even about the both of you; it is about Jesus Christ and the love he has for his Bride, the Church.
A Sacrament is never about an individual person; Sacraments are always about the love of Jesus Christ. Even my ordination day was about me, but about the love that Jesus with us through Confession and the Eucharist.We very often celebrate the Baptism of several infants within the same liturgy; why do we not also often celebrate the wedding of several couples within the same liturgy? Or, at the very least, why do not celebrate weddings within a usual Sunday Mass?